Organic electroluminescence devices (hereinafter, also referred to as “devices” or “organic EL devices”) are capable of obtaining light emission with high luminance intensity with low voltage driving, and thus have been actively researched and developed. Organic electroluminescence devices have an organic layer interposed between a pair of electrodes and utilize, for light emission, energy of the exciton generated as a result of recombination of electrons injected from a cathode and holes injected from an anode in the organic layer.
Improvement in the efficiency of devices has been recently made by using a phosphorescent light emitting material. Further, doping-type devices, which utilize light emitting layers in which a light emitting material is doped in a host material, have been widely employed.
For example, Patent Document 1 describes an organic electroluminescence device using an iridium complexe as a phosphorescent light emitting material, and using a compound containing a carbazole structure and a nitrogen-containing 6-membered aromatic heterocyclic ring as a host material.
Further, development of compounds having an electron transportability has been conducted for the purpose of improving the light emission efficiency and durability of organic electroluminescence devices.
For example, Patent Document 2 describes an organic electroluminescence device in which an electron transporting layer composed of a specific compound containing an anthracene structure and a benzimidazole structure is disposed between a light emitting layer containing a fluorescent light emitting material and a cathode.
In addition, Patent Documents 5 and 6 describe an organic electroluminescence device including a specific compound containing an anthracene structure and a benzimidazole structure.
In addition, Patent Documents 3 and 4 an organic electroluminescence device in which an iridium complexe is used as a phosphorescent light emitting material, and a compound containing a carbazole structure and a nitrogen-containing 6-membered aromatic heterocyclic ring is used as a host material, and in which an electron transporting layer composed of a specific compound containing an anthracene structure and a benzimidazole structure is disposed between a light emitting layer containing a fluorescent light emitting material and a cathode.